250. 
251. 
252. 
Johnson, R. F., Jr. 1976. Mortality 
factors affecting a white pelican pop- 
ulation, Chase Lake National Wildlife 
Refuge, North Dakota. M.S. Thesis. 
Michigan Technological University, 
Houghton. 74 pp. 
Mortality factors responsible for low 
fledging rates of white pelicans in 
North Dakota were studied. Nest aban- 
donment related to water conditions 
and sibling rivalry were major causes 
of poor reproduction. Predation, ac- 
cidents, and physical stress do not 
cause significant mortality in an un- 
disturbed situation, but may become 
significant with extensive and repeat- 
ed human disturbance. 
DISTURBANCE (GENERAL), FISHING, LAKES, 
PREDATION, U.S. NATIONAL WILDLIFE REF- 
UGES, WHITE PELICAN 
Johnson, R. F., Jr., and N. F. Sloan. 
1975. Fishing gear--a deadly hazard. 
Inl. Bird-Banding News 47:115-117. 
During studies of a white pelican pop- 
ulation at Chase Lake National Wild- 
life Refuge, North Dakota, several 
birds were observed to have suffered 
problems from fishing gear. Birds 
were observed entangled with fishing 
line, 1 had a lure embedded in its 
wing muscles, and 1 incubating adult 
was seen with a fish stringer trailing 
from its pouch. 
FISHING, LAKES, U.S. 
REFUGES, WHITE PELICAN 
NATIONAL WILDLIFE 
Johnson, R. F., Jr., and N. F. Sloan. 
1976. The effects of human distur- 
bance on the white pelican colony at 
Chase Lake National Wildlife Refuge, 
North Dakota. Inl. Bird-Banding News 
48: 163-170. 
Human disturbance of a white pelican 
colony was studied in North Dakota. 
Predation on eggs and young by gulls 
was severe when adult birds were kept 
away from nests for long periods. 
Temperature stress to young and stress 
caused by trampling and pod movement 
of older young were also important ef- 
fects of human disturbance. 
DISTURBANCE (GENERAL), LAKES, WETLANDS, 
PREDATION, U.S. NATIONAL WILDLIFE REF- 
UGES, WHITE PELICAN, CALIFORNIA GULL, 
RING-BILLED GULL 
47 
253. 
254. 
255. 
Jonkel, C. 1970. The behavior of cap- 
tured North American bears. BioSci- 
ence 20:1145-1147. 
Observations of wild black bears, 
grizzly bears, and polar bears held in 
snares indicate that only the grizzly 
bear is unusually aggressive. Bears 
appear prone to forming strong habits, 
suggesting that bear behavior research 
can provide a basis for management. 
HUMAN HEALTH AND SAFETY, RECREATION MAN- 
AGEMENT, WILDLIFE MANAGEMENT, THREATENED 
AND ENDANGERED SPECIES, BEARS, GRIZZLY 
BEAR, BLACK BEAR, POLAR BEAR 
Jonkel, C. 1979. Living with grizz- 
lies. Pages 133-137 in R. Lockwood, 
ed. Wildlife survival. Proceedings 
of the 2nd Symposium on Endangered 
North American Wildlife and Habitat, 
1-6 June 1977, St. Louis, Mo. The 
Wild Canid Survival and Research Cen- 
ter, Inc., St. Louis, Mo. 
The status of grizzly bears and prob- 
Jems of coexistence with man in North 
America are described. To coexist 
with grizzlies people must learn to be 
tolerant of bears and to conduct out- 
door activities in ways that reduce 
the possibilities of conflicts with 
bears. Increasing human use of Na- 
tional Parks and other areas contain- 
ing grizzly populations are creating 
new conflicts between humans~ and 
bears. 
HIKING, CAMPING, FISHING, FORESTS, HUMAN 
HEALTH AND SAFETY, THREATENED AND ENDAN- 
GERED SPECIES, WILDLIFE MANAGEMENT, U.S. 
NATIONAL PARKS, GRIZZLY BEAR 
Jonkel, C. J., and C. Servheen. 1977. 
Bears and people: A wilderness man- 
agement challenge. West. Wildlands 
4(2):22-25. 
When grizzly bear-human contacts are 
frequent and do not result in harm to 
the bear, bears can become conditioned 
to humans and may learn to exploit 
such encounters to gain food. Such 
dangerous behavior is becoming a prob- 
Jem in North American National Parks. 
Regulated hunting outside of preserves 
prevents such conditioning; the an- 
swers within parks are some restric- 
tions on backcountry use plus inform- 
ing people about bear behavior and how 
to avoid confrontations. 
